The certificate used on the Data Aggregator only has the fully qualified domain name and the Data Aggregator data source is configured with the hostname or vice versa.
Release : 3.7
Component : IM Reporting / Admin / Configuration
Under Administration->Data Sources->Data Sources.
Select and edit the Data Aggregator (DA) Data source.
Change the hostname to match the contents of the certificate subject alternative name if mismatched,
You must also be able to solve this from CAPC.
Click test and if successful save.
Verify data, etc are present after 1 or 2 sync cycles. It may take some time.
Note the existing DA data source should be changed and saved, the existing DA data source should *never* be removed.